Inverter Maintenance Testing Common Method:
1) Test rectifier circuit
Find the inverter DC power supply inside the P-side and N-side, the multimeter transferred to the resistance X10 file, red table bar connected to the P, black bar, respectively, according to R, S, T, there should be about a few tens of Ohm resistance, And basically balanced. On the contrary, the black table rod connected to the P side, followed by red table bar received R, S, T, there is a close to the infinite resistance. The red table bar connected to the N-side, repeat the above steps, should get the same result. If you have the following results, you can determine the circuit has been abnormal, A resistance three-phase imbalance, can explain the rectifier bridge failure. B. red table rod P terminal, the resistance is infinite, you can conclude that the rectifier bridge failure or starting resistance failure.
2) Test the inverter circuit
The red table bar connected to the P-side, black bars were then U, V, W, there should be dozens of Ohm resistance, and the resistance value of the same basic, reverse should be infinite. Connect the black stick to the N terminal, repeat the above steps should get the same result, otherwise you can determine the inverter module failure.